The present invention is directed to an adjustable armrest for a vehicle seat.
Armrests are frequently employed on vehicle seats, especially in trucks, agricultural vehicles, and other off-road vehicles. The armrest not only provides support for the operator's arm; it also provides lateral support for the body. In both ways, comfort is increased and fatigue is lessened. To obtain maximum benefit from the armrest, it should be adjustable, both as to height and slope. Also, since many vehicles have confined cabs, it is desirable that the armrest have a sufficient range of movement to allow easy access to the vehicle cab and seat. Finally, the armrest mechanism should be simple and rugged to withstand severe working conditions including shocks, dirt or dust, and still require little maintenance.
Attempts have been made to address some of these problems by providing an armrest which can be moved to a variety of positions to allow access to a truck cab, accommodate users of different sizes, and--when fully lowered--increase seat width. Many of these prior art mechanisms are complex and usually require a significant number of parts. Other adjustable armrests provide only a single operable position of the armrest support between the extreme raised and lowered positions, with perhaps the addition of a limited range of vertical movement of the armrest through manually operated knobs. Such a device is described in U.S. Pat. No. 4,097,088 to Meiller.
Available devices also suffer from other disadvantages. Some devices combine the structure which guides the armrest through its vertical or rotary movement with the structure which holds the armrest in a particular position; this can hamper smooth operation of the armrest. Such devices ca also require that a latch or locking mechanism be released separately before moving the armrest assembly in any direction, such as by lifting the armrest before it can otherwise be moved. In still other devices, the locking mechanism must be manually latched or unlatched when moving the armrest assembly through different positions, as is necessary in the folding armrest described in U.S. Pat. No. 4,496,190 to Barley.